Teen heartthrob. Respected actor. Noted dancer. Is there anything Leonardo DiCaprio can’t do? Besides win an Oscar? Well, there’s at least one more thing to scratch off his bucket list: become the United Nations’ new ambassador of peace. What exactly that means is sort of tough to say, but according to UN Secretary General Ban Ki-Moon, Leo is “is not just one of the world’s leading actors,” but he also has “a longstanding commitment to environmental causes.” That’s very true, and DiCaprio’s commitment to raising awareness about the environment does seem to be more than just the usual lip service stars are supposed to pay to a cause …